This invention relates to sprinkler head assemblies, and specifically to an improved apparatus and method of assembly and use for such assemblies, which provide flexibility, economy, and ease of operation to the user.
For cost and other reasons, sprinkler heads are typically constructed from one or more molded plastic pieces. Manufacturing considerations sometimes result in sprinkler heads with two or more plastic members created from relatively simple molds, in contrast to construction of sprinkler heads comprised of a single plastic member from a relatively complex mold. For example, constructing a sprinkler head from a single, complex mold can result in an apparatus with inconsistent structural integrity and other heat characteristics (arising from the heating and cooling of plastic during the molding). Poor structural integrity can result in increased breakage during assembly, packaging, and use; and can thereby decrease the yield of usable products by the manufacturer as well as the user. Although it is known to use two or more relatively simple pieces to fabricate a sprinkler head, numerous shortcomings are still evident in the prior art.
Sprinkler heads have been designed to provide users control of both the volume and direction of water outflow from irrigation systems. Some prior art sprinkler heads contain a water volume control device (typically a threaded device) which also acts to secure the individual members comprising the sprinkler head to one another. Examples include U.S. Pat. No. 4,189,099 (Bruninga); U.S. Pat. No. 4,625,917 (Torney); and 4,739,934 (Gewelber). The use of a single element (such as a threaded device) to both control the volume of water through the sprinkler head and to secure the sprinkler head assembly together can risk damaging the sprinkler head assembly. Among other things, excessive tightening of the water volume adjustment device by the user can inadvertently cause unwanted and excessive stress on that or other sprinkler head components, immediately or eventually causing the plastic sprinkler head to crack and fail or otherwise become unusable.
Some prior art systems (for example, U.S. Pat. No. 4,625,917 (Torney) and U.S. Pat. No. 4,739,934 (Gewelber)) use removable devices (e.g. plugs or tabs) in water outflow channels, to permit an installer or user to control the direction and pattern in which water sprays from the sprinkler head. These flow directing devices are typically designed to withstand the forces of normal household water pressure but can still be selectably removed by the user, as described below. Design considerations in such devices include the number of flow directing tabs or devices, and the relationship between the devices and the water channels in the rest of the sprinkler assembly. Some prior art devices allow the user to selectively adjust the angle in which water sprays from the sprinkler head between 0 and 360 degrees. However, these devices typically are cumbersome and difficult to xe2x80x9csetxe2x80x9d (e.g., remove the tabs or plugs) in the field, as they require the use of additional tools (e.g. a nail, an awl, or a screwdriver), and/or require disassembly of the sprinkler head, for their removal or adjustment.
The use of additional hardware to xe2x80x9csetxe2x80x9d (e.g., remove or adjust) these tabs or flow control devices can also present some physical risk to the user. For example, in the commonly wet handling conditions found when using and installing these sprinkler heads, there is an increased likelihood that the foreign instrument used to remove the tab or flow directing devices (a nail for example), may slip and consequently result in injury to the user.
Furthermore, in sprinkler heads comprised of more than one component, disassembly of the sprinkler head (in contrast to simply unscrewing the head assembly from the irrigation pipe riser) is typically required to gain access to these tabs or flow directing devices. This disassembly increases the time required to make any desired flow adjustments, and also increases the risk that some components may be lost during disassembly and reassembly.
Another shortcoming of certain prior art sprinkler head assemblies comprised of multiple components is the relative difficulty in xe2x80x9caimingxe2x80x9d the water spray in the desired direction. Specifically, certain multi-part prior art devices and assemblies typically lack means to readily and accurately ensure that the individual members of said assemblies are desirably aligned and positioned (and the waterflow is thereby properly directed) without disassembling the sprinkler head apparatus. Commonly, to even test whether the sprinkler head outflow is correctly aimed, a user must permit the water to flow through the system. If the water outflow pattern is incorrect and/or the incorrect water-channel plugs or tabs have been removed, or are not in proper alignment with the corresponding outflow channels, disassembly and reassembly of the sprinkler head may be required (to adjust the waterflow through the head), followed by the subsequent retesting of the water outflow. This procedure is repeated until such time as the desired spray pattern is obtained. The intermittent and repeated testing of water outflow, and the repeated disassembly and reassembly of the sprinkler head is inefficient both in terms of time and manpower.
It is, therefore, an object of my invention to provide an improved sprinkler head apparatus and method of use and assembly of same. The preferred sprinkler head of my invention is characterized by a body assembled from multiple components or members, with attachment means to hold those members assembled to one another independently of controlling water volume flow through the apparatus.
Another object of my invention is the provision of an apparatus of the foregoing character which includes upper and lower components or members, and further includes removable tab members exposed at the lower surface of the lower member of the apparatus. Preferably, the apparatus permits easy removal of the tab members without the need for additional equipment. Subsequent to the initial installation, the preferred flow control tab members can be accessed (and removed as necessary) by simply unscrewing the head assembly from the irrigation pipe riser.
A further object of my invention is the provision of an apparatus of the foregoing character including registration means to facilitate desired alignment between the upper and lower members. Among other things, this preferably permits accurate removal of water direction control members (such as tabs) without the need to disassemble the apparatus (or at least without the need to disassemble the other components from each other).
The preferred embodiment also includes serrations on the apparatus to, among other things, facilitate gripping and manipulation by a user and/or by the person installing the system.
Another object of my invention is the provision of a method to fabricate and assemble members of a sprinkler head assembly of the foregoing character.
A still further object of my invention is the provision of a method of directing irrigation water spray patterns by removing water direction control members from a sprinkler head without additional tools or hardware.
Yet, another object of my invention is the provision of a method of desirably aligning upper and lower members of the sprinkler head assembly of the aforementioned character, to permit predictable water flow through the head. The preferred method and apparatus includes a registration key between the upper and lower members.
Other objects and advantages of my invention will be apparent from the following specification and the accompanying drawings, which are for the purpose of illustration only.